Cleaning method and cleaning equipment for wafer electroplating equipment

Abstract

The invention provides a cleaning method and cleaning equipment for wafer electroplating equipment, and the cleaning method for the wafer electroplating equipment comprises the steps: starting the cleaning equipment to execute first preparation operation in the electroplating process of the wafer electroplating equipment; after the electroplating process of the wafer electroplating equipment is suspended, the cleaning equipment is controlled to execute first cleaning operation so as to at least clean a conducting ring in the wafer electroplating equipment; wherein the difference value between the end time of the first preparation operation and the pause time of the electroplating process is smaller than a preset time difference. According to the invention, by setting the preparation operation and the cleaning operation, the conducting ring can be timely and comprehensively cleaned according to different electroplating process conditions, the wafer is prevented from being polluted by the residual electroplating liquid of the conducting ring, the electroplating equipment is thoroughly cleaned, and the product performance and reliability are improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor equipment, and in particular to a cleaning method and cleaning equipment for wafer electroplating equipment. Background Art

[0002] In the semiconductor manufacturing industry, the wafer manufacturing process places extremely high demands on the purity of the equipment environment. To ensure the cleanliness of semiconductor wafers and the uniformity of electroplating, both the wafers and the electroplating equipment must be cleaned promptly and thoroughly. However, current cleaning processes mostly focus solely on cleaning the wafers themselves, with only a few cases also considering cleaning the electroplating chamber.

[0003] In actual electroplating operations, unavoidable problems often arise. For example, small amounts of plating solution may seep through gaps in components during the plating process, or plating solution may drip onto conductive rings during wafer loading and unloading. While seemingly minor, these issues can potentially impact the entire electroplating process. Existing cleaning methods often fail to thoroughly clean these tiny gaps in the plating chamber, resulting in residual plating solution or impurities that cannot be completely removed.

[0004] Therefore, the conductive ring of the plating head is often overlooked during cleaning. Failure to properly clean the conductive ring can lead to contamination of the plating solution, which in turn affects the resistance value during the plating process and ultimately compromises the plating uniformity of the conductive ring. This unevenness can degrade the plating quality on the wafer surface, impacting the performance and reliability of semiconductor devices.

[0005] It should be noted that the above introduction to the technical background is merely intended to provide a clear and complete description of the technical solutions of this application and facilitate understanding by those skilled in the art. Simply because these solutions are described in the background technology section of this application, it should not be assumed that the above technical solutions are well known to those skilled in the art. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a cleaning method and cleaning equipment for wafer electroplating equipment, so as to solve the problems in the prior art.

[0007] To achieve the above-mentioned and other related purposes, the present invention provides a method for cleaning a wafer electroplating device, comprising:

[0008] During the electroplating process of the wafer electroplating equipment, starting the cleaning equipment to perform a first preparatory operation;

[0009] After the wafer electroplating equipment suspends the electroplating process, the cleaning equipment is controlled to perform a first cleaning operation to at least clean the conductive ring in the wafer electroplating equipment; wherein the difference between the end time of the first preparatory operation and the time of suspending the electroplating process is less than a preset time difference.

[0010] Optionally, the first preparatory operation includes selecting one of the wetting modes and executing the selected wetting mode on the cleaning device to wet the cleaning utensils in the cleaning device according to a preset humidity; wherein each wetting mode is set to a different preset humidity.

[0011] Optionally, each wetting mode includes at least a wetting mode of 0% humidity, a wetting mode of 50% humidity, and a wetting mode of 100% humidity.

[0012] Optionally, the specific steps of executing the selected wetting mode include: setting the time for the nozzle to spray cleaning liquid to the cleaning tool according to the preset time corresponding to the selected wetting mode, and setting the rotation speed of the cleaning tool relative to the conductive ring according to the preset rotation speed corresponding to the selected wetting mode.

[0013] Optionally, the first cleaning operation specifically includes: contacting a cleaning tool in the cleaning equipment with the conductive ring and controlling the cleaning tool to rotate relative to the conductive ring to clean the conductive ring.

[0014] Optionally, the cleaning method further comprises, during the execution of the first preparatory operation, feeding back the flow rate sprayed by the nozzle to the cleaning appliance to correct a control parameter of the first preparatory operation.

[0015] Optionally, during the execution of the first cleaning operation, the contact pressure of the cleaning tool is fed back to correct the control parameters of the first cleaning operation.

[0016] Optionally, the cleaning method further includes a pre-cleaning step, including: before the wafer electroplating equipment performs the electroplating process, starting the cleaning equipment to perform a second preparatory operation and a second cleaning operation to pre-clean the conductive ring.

[0017] Optionally, the wafer electroplating equipment is set to pause the electroplating process and record the number of electroplating times after each electroplating of P wafers, so as to control the cleaning equipment to perform the first cleaning operation, and after the first cleaning operation is completed, start the wafer electroplating equipment to continue the electroplating process; wherein P is an integer greater than or equal to 2.

[0018] Optionally, the cleaning method further includes: after the wafer electroplating equipment completes the electroplating process, controlling the cleaning equipment to perform a self-cleaning operation.

[0019] To achieve the above-mentioned and other related purposes, the present invention provides a cleaning device for implementing the cleaning method of the wafer electroplating device, the cleaning device comprising:

[0020] A cleaning equipment body and a cleaning tool; the cleaning tool is arranged at the first end of the cleaning equipment body and is used to clean at least the conductive ring in the wafer electroplating equipment.

[0021] Optionally, the cleaning equipment also includes a nozzle and a rotating mechanism; the nozzle is arranged near the first end of the cleaning equipment body and is set at a preset distance from the cleaning tool; the nozzle is used to spray cleaning liquid onto the cleaning tool; the rotating mechanism is arranged through the cleaning equipment body, and is used to control the rotation of the cleaning tool relative to the wafer electroplating equipment.

[0022] Optionally, the cleaning tool includes a disc, an air bag and a cleaning sheet;

[0023] The diameter of the disc is larger than the inner diameter of the conductive ring and smaller than the diameter of the conductive ring; the airbag is mounted on the disc, and the contact pressure between the conductive ring and the cleaning tool is regulated based on the air pressure of the airbag; the airbag is provided with a cleaning sheet for frictionally cleaning the conductive ring.

[0024] Optionally, the surface of the disk close to the conductive ring is further provided with M grooves; M is an integer greater than or equal to 1; strain gauges are accommodated in the grooves for converting the contact pressure into an electrical signal and feeding it back to the cleaning device.

[0025] As described above, the cleaning method and cleaning equipment of the wafer electroplating equipment of the present invention have the following beneficial effects:

[0026] The present invention ensures that the cleaning conductive ring can be cleaned in a timely and all-round manner according to different electroplating process conditions by setting up preparatory operations and cleaning operations, preventing the wafer from being contaminated by the electroplating liquid remaining in the conductive ring, thoroughly cleaning the electroplating equipment, and improving product performance and reliability. At the same time, according to different process conditions and different electroplating liquid components, a variety of cleaning liquids can be used through the nozzle to wet the cleaning tool to different degrees, and the number and frequency of cleaning the conductive ring by the cleaning tool can be adjusted according to demand to ensure that the conductive ring is clean and achieve the best cleaning effect for the conductive ring, and has extremely high adjustability and adaptability. In addition, the present invention is also provided with pressure feedback and flow feedback, which can adaptively adjust the cleaning liquid in the cleaning process to ensure the cleaning effect and the recyclability of the cleaning tools. The overall device has a simple structure, a simple method, and a low cost, which is convenient for large-scale promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1Shown is a schematic diagram of the steps of the cleaning method of the wafer electroplating equipment of the present invention.

[0028] Figure 2 Shown is a schematic structural diagram of the cleaning equipment of the present invention.

[0029] Figure 3 Shown is a schematic diagram of the appearance of the cleaning tool of the present invention.

[0030] Figure 4 Shown is a schematic structural diagram of the strain gauge of the present invention.

[0031] Figure 5 Shown is a side schematic diagram of the strain gauge of the present invention.

[0032] Figure 6 Shown is a schematic structural diagram of the nozzle of the present invention.

[0033] Component number description

[0034] 1 Wafer electroplating equipment

[0035] 10 Electroplating head body

[0036] 11 Conductive ring

[0037] 2. Cleaning equipment

[0038] 21 Cleaning utensils

[0039] 211 disc

[0040] 2111 strain gauge

[0041] 212 Airbag

[0042] 213 cleaning tablets

[0043] 22 nozzles

[0044] 23 Rotating mechanism

[0045] 24 cleaning chamber DETAILED DESCRIPTION

[0046] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0047] See also Figures 1 to 6It should be noted that the diagrams provided in this embodiment are merely schematic illustrations of the basic concept of the present invention. Therefore, the diagrams only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0048] During the cleaning process of wafer electroplating equipment, the conductive ring must be cleaned to prevent subsequent wafers from being contaminated by the plating solution during repeated use. However, the connection between the conductive ring and the plating head of the wafer electroplating equipment has many tiny gaps, making the cleaning process after disassembly of the conductive ring cumbersome. Furthermore, it is difficult to reach the tiny gaps during cleaning, resulting in poor cleaning results.

[0049] Therefore, the present invention provides a cleaning device 2 that can be set at the position where the wafer is electroplated without removing the conductive ring, so as to perform cleaning. However, in actual use, the cleaning effect of such a cleaning device still needs to be further optimized. The cleaning device 2 is not well compatible with wafer electroplating equipment under different electroplating processes, as well as wafer electroplating equipment in different states. For example, if a relatively wet device is used for friction cleaning of a wafer electroplating equipment that has just completed the electroplating process, the friction force of the friction cleaning will be reduced due to excessive water during cleaning, thereby reducing the cleaning effect and may aggravate local corrosion due to excessive steam generated by high temperature; or, if a relatively wet device is not used for friction cleaning of a wafer electroplating equipment that has been completed for a long time due to the electroplating process, there will be too little water during cleaning, resulting in insufficient cleaning liquid to dilute and dissolve the residual electroplating liquid well, affecting the cleaning effect.

[0050] To further optimize the cleaning effect, Figure 1 As shown, this embodiment provides a method for cleaning a wafer electroplating device, based on Figures 2 to 6 The cleaning device 2 shown in the figure is implemented as follows. The cleaning device 2 of this embodiment includes: a cleaning device body and a cleaning tool 21.

[0051] The wafer electroplating apparatus 1 includes a plating head body 10 and a conductive ring 11 disposed at the lower end of the plating head body 10. The conductive ring 11 is hollow in the middle to expose the center of the wafer. The contact portion between the conductive ring 11 and the plating head body 10 is used to clamp the edge of the wafer to facilitate electroplating.

[0052] like Figures 2 to 6 As shown, the cleaning tool 21 is arranged at the first end of the cleaning equipment body, and is used to clean at least the conductive ring 11 in the wafer electroplating equipment 1.

[0053] In this embodiment, the cleaning equipment body is arranged to pass through the central axis of the electroplating head body 10, and the cleaning tool 21 is clamped between the electroplating head body 10 and the conductive ring 11 to clean at least the upper surface of the conductive ring 11 and the lower surface of the electroplating head body 10.

[0054] Specifically, if Figures 2 to 5 As shown, the cleaning tool 21 includes a disc 211 , an air bag 212 and a cleaning sheet 213 .

[0055] As an example, the diameter of the disc 211 is larger than the inner diameter of the conductive ring 11 and smaller than the diameter of the conductive ring, making it easier to place the disc 211 in the cavity between the conductive ring 11 and the ferry head, facilitating subsequent cleaning operations and preventing the disc 211 from falling through the opening in the inner diameter of the conductive ring due to its small diameter. An airbag 212 is mounted on the disc 211, and the contact pressure between the conductive ring and the cleaning fixture 21 is regulated based on the air pressure of the airbag 212. A cleaning sheet 213 is mounted on the outside of the airbag 212 for frictionally cleaning the conductive ring 11. In this embodiment, during the cleaning operation, the cleaning fixture 21 replaces the wafer and is clamped between the conductive ring 11 and the electroplating head body 10, facilitating cleaning of the lower surface of the conductive ring 11 and the upper surface of the electroplating head body 10. This prevents a small amount of plating solution from seeping into or dripping onto the conductive ring during the electroplating process or during the wafer loading and unloading process, which makes it difficult to clean directly, resulting in contamination of the plating solution, affecting the resistance, and ultimately affecting the uniformity of the conductive ring 11. The cleaning sheet is made of any hydrophilic fiber material, such as cotton, to ensure that it can absorb stains and provide mechanical friction during the cleaning process.

[0056] As an example, the surface of the disk 211 close to the conductive ring 11 is also provided with M grooves (not shown in the figure); M is an integer greater than or equal to 1; the grooves accommodate strain gauges 2111 for converting contact pressure into electrical signals and feeding them back to the cleaning device 2.

[0057] In this embodiment, a pressure sensor is integrated between the conductive ring 11 and the cleaning appliance 21 to monitor the contact pressure in real time and automatically adjust the pressure based on feedback to maintain the optimal contact state. Preferably, a plurality of thin metal sheet grooves are evenly distributed on the disc 211, and strain gauges 2111 are pasted into the grooves with an insulating adhesive. When the airbag 212 presses the fiber material, the strain gauge 2111 deforms, causing the resistance of the strain gauge 2111 to change, resulting in a change in the voltage across the strain gauge 2111 as a voltage divider resistor. The strain calibrated according to the voltage change can obtain the real-time stress change. In this way, the evenly distributed strain gauge can obtain the stress change at multiple points of the cleaning appliance 21. The strain gauge 2111 is fed back to the control unit (not shown in the figure) in the cleaning device 2 by means of an electrical connection. The airbag is designed to be inflated, and the inflation pressure can be adjusted according to the stress at multiple points. In another example, the corresponding strain gauge 2111 can also be directly pasted on the disc 211 for transmission.

[0058] It should be noted that the size, shape, and placement of the strain gauges 2111 can be arbitrarily configured, as long as the strain gauges 2111 can provide feedback on the contact pressure of the cleaning fixture 21, facilitating adjustment of pressure changes in the airbag. Furthermore, each strain gauge 2111 can independently transmit an electrical signal or transmit a modified aggregate signal via a series-parallel configuration. The signal transmission path and method can be configured as needed and are not limited to this embodiment.

[0059] like Figures 2 to 5 As shown, the cleaning device 2 further includes a nozzle 22 and a rotating mechanism 23 .

[0060] Specifically, if Figure 5 As shown, the nozzle 22 is arranged near the first end of the cleaning device body 20 and is at a preset distance from the cleaning tool 21. The nozzle 22 is used to spray cleaning liquid onto the cleaning tool 21. In another example, the nozzle 22 is used to spray cleaning liquid onto the conductive ring 11, for rinsing the lower surface of the conductive ring 11, and at the same time cooperating with the cleaning tool 21 to clean the upper surface of the conductive ring 11. In this embodiment, the cleaning tool 21 before and after cleaning the conductive ring 11 is transferred to the top of the nozzle by the robot, so that the nozzle sprays the rinse solution or pure water onto the cleaning tool. In this embodiment, the nozzle 22 is arranged at the upper end of the cleaning chamber 24, and the angle is adjustable to facilitate adjustment of the liquid emission direction. The cleaning chamber 24 is used to accommodate excess liquid that splashes and flows out during the cleaning process.

[0061] Specifically, the rotating mechanism 23 is set through the cleaning equipment body 20, and is used to control the rotation of the cleaning tool 21 relative to the wafer electroplating equipment 1. In this embodiment, the driving part is composed of a hollow shaft, a motor rotor and a motor stator. Among them, the motor rotor is sleeved on the outside of the hollow shaft, and the motor stator is sleeved on the outside of the motor rotor. The motor rotor is connected to the conductive ring through structures such as the spring assembly inside the electroplating head. When the motor stator is energized, the motor rotor will rotate accordingly and drive the conductive ring 11 to rotate together. However, the hollow shaft does not rotate with the rotation of the motor rotor, but always remains fixed. At this time, the air bag 152 is provided with an inflation tube on the hollow shaft, so that the inflation tube can smoothly enter the interior of the electroplating head body 10 from the outside, making it convenient to connect the external inflation device to the air bag for inflation.

[0062] In this embodiment, a fixing part is also provided in the electroplating head body 10. The fixing part can be a solenoid valve or a mechanical lock, which is used to fix the cleaning tool 21 in contact with the conductive ring 11 when the conductive ring 11 is in a rotating state, so as to prevent the cleaning tool 21 from rotating with the conductive ring 11 under the action of friction, thereby realizing the rotation of the cleaning tool 21 relative to the conductive ring 11.

[0063] The following is a brief description of the working process of the cleaning tool 21 in this embodiment: after the cleaning tool 21 is directly loaded on the electroplating head body 11, the disc 211 is fixed by a fixing part, and the airbag 212 is connected to the external inflation device through an inflation tube (not shown in the figure); the airbag 212 is inflated until the air pressure in the airbag 212 reaches a preset value; the rotating mechanism 23 is started so that the conductive ring 11 rotates relative to the cleaning sheet 213; after the conductive ring 11 rotates for a preset time, the cleaning tool 21 is removed from the electroplating head body 10; the cleaning tool 21 is cleaned and the cleaning sheet 213 is replaced; the above steps are repeated 3 to 5 times to ensure that the cleaning tool 21 completes a single operation.

[0064] Based on the above cleaning device 2, this embodiment provides a cleaning method for a wafer electroplating device, including:

[0065] like Figure 1 As shown, in step S1, during the electroplating process of the wafer electroplating equipment 1, the cleaning equipment 2 is started to perform a first preparatory operation; wherein the difference between the end time of the first preparatory operation and the pause time of the electroplating process is less than the preset time difference.

[0066] Specifically, in this embodiment, the preset time difference is set to 0.5min to 10min, such as a time difference of 45s, 1min, 5min, etc., and is preferably set to 2min. By setting the preset time difference, it is ensured that the first preparatory operation can be quickly switched to perform the corresponding cleaning work after the wafer electroplating equipment 1 suspends the electroplating process, thereby improving the cleaning power and saving process time. At the same time, in this embodiment, the problem of possible deviation in the preparatory operation due to the cleaning work starting too long after the end of the first preparatory operation can be avoided.

[0067] Specifically, the first preparatory operation includes selecting one of the wetting modes and executing the selected wetting mode on the cleaning device to wet the cleaning utensils 21 in the cleaning device 2 according to a preset humidity; wherein each wetting mode is set to a different preset humidity.

[0068] In this embodiment, after the electroplating process begins and before the cleaning apparatus 2 begins cleaning, it is necessary to control the cleaning device to enter a standby state, including wetting the cleaning tools 21 in the cleaning apparatus 2 to a preset humidity. Each wetting mode has a different preset humidity, and the cleaning apparatus is controlled to reach different humidity levels by switching between different wetting modes. It should be noted that in this embodiment, a single mode can be set to achieve the preset humidity of the cleaning tools 21. In another embodiment, the wetting mode can be adjusted multiple times to achieve the appropriate humidity for subsequent cleaning.

[0069] More specifically, each wetting mode includes at least a wetting mode of 0% humidity, a wetting mode of 50% humidity, and a wetting mode of 100% humidity. Among them, before the cleaning equipment 2 cleans the conductive ring, different wetting modes can be set according to process requirements, including at least three modes: a "dry" mode (0% humidity) without wetting, a "semi-dry" mode (50% humidity) with 50% humidity wetting with cleaning fluid, and a "wet" mode (100% humidity) in which the cleaning fluid is completely wetted but the cleaning fluid does not drip. The cleaning fluid can select different components based on the plating fluid selected by the wafer electroplating equipment 1. By using at least three different wetting modes, it is ensured that the cleaning utensil 21 can contact the conductive ring with different humidity.

[0070] It should be noted that different humidity modes can be selected based on actual processing needs: in the scenario where the conductive ring of the wafer electroplating equipment 1 is contaminated by the plating liquid for a long time, a lower humidity mode is selected. Low humidity can inhibit further oxidation and corrosion of the residual liquid, and can also increase the cleaning friction, such as selecting 0% humidity to rub and clean other impurities on the surface of the conductive ring; in the short-term contamination scenario in the wafer electroplating equipment 1, by increasing the appropriate humidity (such as selecting 50% humidity), the friction is ensured to be relatively sufficient and the impurities attached to the auxiliary conductive ring are dissolved; when the wafer electroplating equipment 1 has just finished electroplating (the equipment is still in a high temperature and high humidity state), the high temperature will accelerate the evaporation of water, and excessive humidity will easily form steam condensation, aggravating local corrosion. Low humidity can shorten the drying time and prevent residual liquid from crystallizing; after the wafer electroplating equipment 1 has finished electroplating for a long time (the equipment has been cooled and dried), appropriate humidity can soften the crystallized contaminants to ensure better cleaning of the conductive ring afterwards. This embodiment sets the cleaning tools 21 with different humidity modes to ensure that the conductive rings of different wafer electroplating equipment 1 have different adsorption capabilities, friction forces and dissolution capabilities, which can be better applied in this field.

[0071] It should be further explained that, for different electroplating processes, a variety of cleaning solutions are used to clean the cleaning tools to further optimize the cleaning effect.

[0072] As an example, the specific steps for executing the selected wetting mode include: setting the time for the nozzle to spray cleaning liquid to the cleaning tool according to the preset time corresponding to the selected wetting mode, and setting the rotation speed of the cleaning tool relative to the conductive ring 11 according to the preset rotation speed corresponding to the selected wetting mode.

[0073] In this embodiment, the flow rate of the cleaning liquid sprayed by the nozzle is relatively fixed, and the humidity of the cleaning ware is controlled by adjusting the spraying time. At the same time, since the cleaning ware rotates relative to the wafer electroplating equipment, the rotation speed can be adjusted to ensure the uniformity of the cleaning liquid sprayed by the nozzle on the one hand, and to avoid splashing of the cleaning liquid due to excessive rotation speed on the other hand.

[0074] like Figure 1 As shown, in step S2, after the wafer electroplating equipment suspends the electroplating process, the cleaning equipment is controlled to perform a first cleaning operation to at least clean the conductive ring in the wafer electroplating equipment.

[0075] Specifically, the first cleaning operation includes: contacting the cleaning tool 21 in the cleaning equipment with the conductive ring 11 and controlling the cleaning tool 21 to rotate relative to the conductive ring 11 to clean the conductive ring.

[0076] As an example, after the electroplating process is completed, the cleaning equipment 2 performs the conductive ring cleaning work. According to the program settings, the cleaning tool 21 in the cleaning equipment 1 is transferred to the plating head of the wafer electroplating equipment 1 by the robot arm. The plating head is opened and closed to contact and clamp the cleaning tool 21 with the conductive ring 11. Subsequently, the cleaning tool 21 is controlled to rotate relative to the conductive ring 11 to ensure subsequent cleaning.

[0077] Furthermore, in this embodiment, the cleaning device 21 includes a disc 211, an airbag 212, and a cleaning sheet 213. The diameter of the disc 211 is larger than the inner diameter of the conductive ring 11 and smaller than the diameter of the conductive ring. The airbag 212 is mounted on the disc 211, and the air pressure in the airbag regulates the contact pressure between the conductive ring 11 and the cleaning device 21. The cleaning sheet 213 is mounted on the outside of the airbag 212 for friction cleaning of the conductive ring 11. In this embodiment, by inflating the airbag 212, the cleaning sheet (a fiber cotton sheet in this embodiment) contacts the conductive ring 11, and the residual electroplating solution on the conductive ring is cleaned through capillary force and mechanical flexible friction.

[0078] In this embodiment, the cleaning method of the wafer electroplating equipment further includes, during the execution of the first preparatory operation, feeding back the flow rate of the nozzle spraying the cleaning tool 21 to correct the control parameters of the first preparatory operation.

[0079] In this embodiment, the cleaning method of the wafer electroplating equipment further includes, during the execution of the first cleaning operation, feeding back the contact pressure of the cleaning tool 21 to correct the control parameters of the first cleaning operation.

[0080] In this embodiment, by detecting the spray flow rate and the pressure of the cleaning tool contacting the conductive ring 11, a more uniform distribution of the liquid is achieved, thereby improving the rinsing effect. Furthermore, through real-time detection, if it is found that the contact pressure or flow rate does not reach the preset value, the preset pressure parameters during the cleaning process and the spray parameters during the preparatory operation can be adjusted to adapt to different working environments and needs.

[0081] Specifically, the wafer electroplating equipment 1 is set to suspend the electroplating process after each electroplating of P wafers, where P is an integer greater than or equal to 2; to control the cleaning equipment to perform the first cleaning operation, and after the first cleaning operation is completed, start the wafer electroplating equipment 1 to continue the electroplating process.

[0082] In this embodiment, the wafer electroplating apparatus 1 continuously electroplates multiple wafers during the wafer electroplating process. To prevent the conductive ring 11 from being contaminated by the plating solution and not being cleaned promptly, which would result in unwanted contamination on the subsequently plated wafers, the conductive ring 11 is required to be cleaned after a certain number of wafers have been plated. This is done by increasing the frequency of cleaning to avoid further contamination. It should be noted that the frequency of cleaning, i.e., the value of P, can be adjusted according to process requirements.

[0083] In this embodiment, the electroplating process of the wafer electroplating apparatus 1 is considered to be completely completed when the number of electroplating cycles reaches a certain preset value. In another embodiment, the electroplating process of the wafer electroplating apparatus 1 is considered to be completely completed when all wafers in the batch are electroplated. The actual termination conditions are not limited to this embodiment.

[0084] like Figure 1 As shown, the cleaning method of the wafer electroplating equipment further includes a pre-cleaning step S0, including: before the wafer electroplating equipment 1 performs the electroplating process, starting the cleaning equipment 2 to perform a second preparatory operation and a second cleaning operation to pre-clean the conductive ring.

[0085] Specifically, in this embodiment, when the wafer electroplating equipment 1 is turned from the off state to the on state but the electroplating is not started, the cleaning equipment remains in the on state. Regardless of whether the conductive ring 11 is clean, the process of cleaning the conductive ring 11 can be completed. On the one hand, it tests whether the cleaning equipment 2 can have a fault; on the other hand, it ensures the purity of the wafer electroplating equipment 1.

[0086] The pre-cleaning step S0 still requires that the cleaning device 2 sequentially execute the second preparatory operation and the second cleaning operation. The cleaning device 2 must first be set to execute the selected wetting mode before cleaning the conductive ring 11. In this embodiment, the second preparatory operation and the second cleaning operation can be configured similarly to the first preparatory operation and the first cleaning operation described above, and will not be further detailed here.

[0087] like Figure 1 As shown, step S4, the cleaning method of the wafer electroplating equipment further includes controlling the cleaning equipment 2 to perform a self-cleaning operation after the wafer electroplating equipment 1 completes the electroplating process.

[0088] In this embodiment, after cleaning is completed, the plating head of the wafer electroplating equipment 1 is opened and closed according to the program settings, the cleaning tool 21 of the cleaning equipment is released, and the cleaning tool 21 is transferred to the cleaning chamber 24 by a robot arm, and the surface is cleaned through processes such as spraying water from a nozzle and drying, in preparation for subsequent use.

[0089] It should be noted that after the second preparatory operation and the second cleaning operation are completed, the cleaning device 2 may be controlled to perform a self-cleaning operation again to avoid possible contamination during subsequent cleaning processes.

[0090] It should be further explained that this embodiment sets multiple time nodes, namely before cleaning, after cleaning, before electroplating, and after electroplating, corresponding to different processes, to ensure that the cleaning device 2 is in good working condition and the cleaning of the conductive ring 11 is completed in a timely manner. This embodiment can be adapted to the cleaning of different wafer electroplating processes.

[0091] In summary, the present invention provides a cleaning method and cleaning equipment for wafer electroplating equipment, wherein the cleaning method for wafer electroplating equipment comprises: during the electroplating process of the wafer electroplating equipment, starting the cleaning equipment to perform a first preparatory operation; after the wafer electroplating equipment suspends the electroplating process, controlling the cleaning equipment to perform a first cleaning operation to at least clean the conductive ring in the wafer electroplating equipment; wherein the difference between the end time of the first preparatory operation and the suspension time of the electroplating process is less than a preset time difference. The present invention ensures that the clean conductive ring can be cleaned in a timely and all-round manner for different electroplating process conditions by setting preparatory operations and cleaning operations, thereby preventing the wafer from being contaminated by the electroplating solution remaining in the conductive ring, thoroughly cleaning the electroplating equipment, and improving product performance and reliability. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.

[0092] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A method for cleaning a wafer electroplating device, characterized in that: The cleaning method comprises: During the electroplating process of the wafer electroplating equipment, starting the cleaning equipment to perform a first preparatory operation; After the wafer electroplating equipment suspends the electroplating process, controlling the cleaning equipment to perform a first cleaning operation to at least clean the conductive ring in the wafer electroplating equipment; Wherein, the difference between the end time of the first preparatory operation and the pause time of the electroplating process is less than a preset time difference.

2. The cleaning method of wafer electroplating equipment according to claim 1, characterized in that: The first preparatory operation includes selecting one of the wetting modes and executing the selected wetting mode on the cleaning device to wet the cleaning utensils in the cleaning device according to a preset humidity; wherein each wetting mode is set to a different preset humidity.

3. The cleaning method of wafer electroplating equipment according to claim 2, characterized in that: The respective wet modes include at least a wet mode of 0% humidity, a wet mode of 50% humidity, and a wet mode of 100% humidity.

4. The cleaning method of wafer electroplating equipment according to claim 2 or 3, characterized in that: The specific steps of executing the selected wetting mode include: setting the time for the nozzle to spray cleaning liquid to the cleaning tool according to the preset time corresponding to the selected wetting mode, and setting the rotation speed of the cleaning tool relative to the conductive ring according to the preset rotation speed corresponding to the selected wetting mode.

5. The cleaning method of wafer electroplating equipment according to claim 4, characterized in that: The first cleaning operation specifically includes: contacting a cleaning tool in the cleaning equipment with the conductive ring and controlling the cleaning tool to rotate relative to the conductive ring to clean the conductive ring.

6. The method for cleaning a wafer electroplating device according to claim 4, wherein: The cleaning method further includes, during the execution of the first preparatory operation, feeding back the flow rate sprayed by the nozzle to the cleaning appliance to modify a control parameter of the first preparatory operation; And / or, during the execution of the first cleaning operation, the contact pressure of the cleaning tool is fed back to correct the control parameters of the first cleaning operation.

7. The cleaning method of wafer electroplating equipment according to claim 1, characterized in that: The cleaning method further includes a pre-cleaning step, which includes: before the wafer electroplating equipment performs the electroplating process, starting the cleaning equipment to perform a second preparatory operation and a second cleaning operation to pre-clean the conductive ring.

8. The method for cleaning wafer electroplating equipment according to claim 1, wherein: The wafer electroplating equipment is configured to pause the electroplating process each time after electroplating P wafers, so as to control the cleaning equipment to perform the first cleaning operation, and after the first cleaning operation is completed, start the wafer electroplating equipment to continue the electroplating process; wherein P is an integer greater than or equal to 2.

9. The method for cleaning a wafer electroplating device according to claim 8, wherein: The cleaning method further includes: controlling the cleaning equipment to perform a self-cleaning operation after the wafer electroplating equipment completes the electroplating process.

10. A cleaning device for implementing the cleaning method of wafer electroplating equipment according to any one of claims 1 to 9, characterized in that: The cleaning equipment comprises: A cleaning equipment body and a cleaning tool; the cleaning tool is arranged at the first end of the cleaning equipment body and is used to clean at least the conductive ring in the wafer electroplating equipment.

11. The cleaning device according to claim 10, characterized in that: The cleaning device also includes a nozzle and a rotating mechanism; The nozzle is arranged near the first end of the cleaning device body and is at a preset distance from the cleaning appliance; the nozzle is used to spray cleaning liquid onto the cleaning appliance; The rotating mechanism is arranged throughout the cleaning equipment body and is used to control the cleaning tool to rotate relative to the wafer electroplating equipment.

12. The cleaning device according to claim 10 or 11, characterized in that: The cleaning tool includes a disc, an air bag and a cleaning sheet; The diameter of the disc is larger than the inner diameter of the conductive ring and smaller than the diameter of the conductive ring; the airbag is mounted on the disc, and the contact pressure between the conductive ring and the cleaning tool is regulated based on the air pressure of the airbag; the airbag is provided with a cleaning sheet for frictionally cleaning the conductive ring.

13. The cleaning device according to claim 12, characterized in that: The surface of the disk close to the conductive ring is further provided with M grooves; M is an integer greater than or equal to 1; strain gauges are accommodated in the grooves for converting the contact pressure into electrical signals and feeding them back to the cleaning device.

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